The fireworks we set off on the Fourth of July are, yes, dangerous, but they are highly engineered pyrotechnic displays that have quite a bit of science behind them. The big bursts you see in the night sky are engineered in several stages. The lift charge, main fuse, and launch tube together are a rocket that gets the firework up in the sky. The largest displays can have shells three feet wide and fly as high as 1000 feet!
Once it get up there, the fuse is crucial, for the timing of the explosion. The burst charge stage then explodes at the specified height, and throw stars. These stars can be any color, depending on the chemicals used. But they may actually burn in a color different from what the human eye sees! There's more going on inside a fireworks shell than meets the eye, and you can read the science behind our Fourth of July fireworks at Big Think.
(Imagecredit: Jeffrey Pang)
